1. Field of The Invention
The invention is directed to a sterile connector used to connect a line to a container filled with a medicinal liquid, and, in particular, a sterile connector with a removable protective cap used to connect a line to a container filled with a medicinal liquid.
2. Description of Related Technology
A film bag for medicinal liquids with a sterile connector for connection to a hose line is known from U.S. Pat. No. 4,201,406. The connector has a tube-like coupler which is sealed with a puncturable membrane. The membrane of the known connector is a plastic sheet, which is a one-piece component of the coupler. The hose line to be connected to the connector has a plunge pin, also referred to as a spike. The spike is surrounded concentrically by a tubular element that can be slid onto the coupler. The plunge pin is pushed into the coupler for connection of the hose line, so that the membrane is punctured and fluid connection is produced between the bag interior and the hose line connected to the spike.
The film bag can be sealed in sterile fashion with the known connector, but it has proven a drawback that the part of the coupler lying in front of the membrane is unprotected. A hazard therefore exists that germs will be introduced to the bag during puncturing of the membrane.
Connectors with releasable plastic closures, for example, screw caps, are also known. However, it has been shown in practice that during sterilization of connectors closed with screw caps in autoclaves, the hazard of leakage exists. O-rings made of silicone have therefore often been used, which seal any gap which may occur during sterilization. A disadvantage of this structure is that silicone rings are relatively expensive to produce in terms of the required purity of the material. Moreover, assembly of the connector is complicated because of the additional sealing elements required.
German Laid-Open Application 2458220 describes a sterile connector, comprising a tubular bottom and a tubular top, which encloses a puncturable membrane that is a one-piece component of the top. The bottom of the coupler is sealed to the bag, and the bag is filled through the opening of the bottom. After filling of the bag, the top is inserted into the bottom, the top and bottom mating via flanges that are sealed to each other. A tear-off closure cover is provided on the top of the coupler to cover the puncture opening.
European Patent Publication No. 732 114 describes a film bag for a liquid for intravenous feeding which has a connector applied to the film bag from the outside. The essentially tubular connector has a flange on its end on the bag side, which lies flatly on the outside of the bag film. In the known connector, the puncturable membrane is formed by the film of the bag itself. During insertion of the plunge pin into the connector, the bag film is punctured so that the fluid connection to the bag interior is produced. A sleeve nut that is screwed onto the tubular connector is provided to secure the plunge pin.
Film bags with a connector whose membrane consists of the bag film itself are generally filled aseptically, i.e., the bags are no longer sterilized in autoclaves after filling. An advantage of this film bag lies in the improved gas impermeability of the entire container, since the bag contents are fully closed by the gas-tight film. However, a shortcoming is that the connector, generally consisting of polyethylene, cannot be sealed to the outer layer of the bag film that generally consists of PET (polyethylene terephthalate), but only glued. This type of glue connection, however, generally leads to poorer production safety than a sealed joint.
A coupler for a flexible film bag that is sealed by a membrane is known from European Patent Publication No. 493 723. The membrane can be punctured with a plunge pin integrated in the protective cap. It is proposed for improvement of the gas barrier that the membrane be a film, which is sealed to the bottom of the coupler.
It is an object of the present invention is to devise a connector suitable for sterilization in autoclaves that offers high safety against contamination of the container, is easily handled and can be produced in large numbers cost-effectively.
According to an aspect of the invention, a sterile connector is provided including a coupler, a protective cap, and a puncturable membrane film. The coupler has a tubular top with an upper edge defining an inwardly facing continuous shoulder, and a mounting piece connected to the inwardly facing continuous shoulder and adapted to sealably receive a plunge pin. The coupler also has a bottom insertable into a container having wall and sealable to the container wall. The coupler further includes a channel-like passage extending between the top and the bottom. The protective cap is attached to the tubular top of the coupler to seal the top, and has a lower edge connected to the continuous shoulder to define an annular rupture zone. The puncturable membrane film is sealed to the bottom of the coupler to close the channel-like passage.
According to another aspect of the invention, a container may be attached to the bottom of the coupler of the connector to define an assembly.